jakman85andClaude Opus 5
9a4489b733
Every oauth2-proxy on this platform is an independent instance with its OWN
cookie-secret. Measured on prod 2026-09-30: seven `*-oauth2-proxy` Secrets, seven
DISTINCT cookie-secret values (compared in-cluster, never printed). So no instance
can DECRYPT another's cookie -- it can only OVERWRITE it.
All of them were emitting oauth2-proxy's DEFAULT names (`_oauth2_proxy`,
`_oauth2_proxy_csrf`) scoped to `.${BASE_DOMAIN}`, so the browser kept ONE cookie
pair for SIX live instances (jackett, pihole, qbittorrent, radarr, sonarr, and the
shared forward-auth proxy). Whichever authenticated last clobbered the rest; the
loser logged `No valid authentication in request`, bounced to Keycloak, and -- the
SSO session still being live -- was redirected straight back and clobbered it again.
The symptom is "I signed into Keycloak but I'm still not signed in", which sends you
hunting in Keycloak, where nothing is wrong. Crafty was fixed on its own side on
2026-09-29 (#22); this is that fix generalized to the pattern.
THE DEFECT WAS NOT IN THE MANIFESTS. apps/wave-*/{jackett,pihole,qbittorrent,radarr,
sonarr}.yaml are GENERATED goldens; one function emits all five. So the fix is in
catalog/render.py::_oauth2_sidecar_container(), and both flags are now DERIVED from
the ServiceDefinition rather than defaulted:
--cookie-name=_oauth2_proxy_{s['name']} unique by construction
--cookie-domain={host} the app's own host, not the zone
A per-service table was rejected for the reason twelve ServiceMonitors once acquired
one identical wrong port name in a single edit: it would leave the NEXT app onboarded
defaulting straight back into the collision. --whitelist-domain stays zone-wide; it
governs post-login REDIRECT targets, not cookie scope.
Host-scoping is defence in depth and is asserted deliberately: a zone-wide cookie is
transmitted by the browser to every host in the zone, so each app's session token was
being sent to every sibling -- and it is what would make a FUTURE name collision
platform-wide instead of contained.
New gate check (whole-repo scope, so it runs on EVERY gate invocation, not only when
a touched path happens to attribute an identity requirement):
conformance/tests/l0-static/oauth2-proxy-cookie-names-distinct/
It resolves each instance's EFFECTIVE cookie name -- declared, or oauth2-proxy's
built-in default when omitted, because an omitted flag is not an absence but a CLAIM
on a name, and reading it as an absence is exactly why this survived five reviews.
Then: no two collide; none is another's name + `_csrf` (oauth2-proxy derives the CSRF
cookie that way); the default has exactly ONE owner, registered with its reason in a
shrink-only register -- the SHARED proxy, which MUST keep `_oauth2_proxy` because
renaming it signs every other gated surface out at once; every other instance is
host-scoped; render.py derives rather than lists; and the SHIPPED renderer is proven
end-to-end on two synthetic ServiceDefinitions, so the check stays falsifiable once
the tree is clean.
Tested in both directions: rc 0 on this tree (39 assertions, 7 instances), rc 1 with
26 failures against the pre-fix tree, plus one targeted mutation per assertion class
(duplicate name, CSRF derivation, zone-wide domain, unregistered default heir, stale
register entry) -- each fired, and nothing else did.
Also regenerates the three L1 rendering goldens, which are expected-output fixtures
of the same renderer.
UNVERIFIED: no browser round-trip. The collision has still never been REPRODUCED in a
browser -- doing so needs two gated apps visited in one session -- so this is reasoned
from measured configuration and from the mechanism, not from a failure anyone watched.
Nothing was applied; merging rolls five Deployments and invalidates every existing
session on them once. See decisions/2026-09-30-oauth2-proxy-cookie-collision-fleet.md.
Co-Authored-By: Claude Opus 5 (1M context) <[email protected]>
decisions/ — the handoff log, one file per entry
This directory is the decision log. ../DECISIONS-LOG.md is the frozen archive of
everything written before 2026-09-29 and is never edited again (see "The archive is
frozen" below).
Why this exists
DECISIONS-LOG.md was append-only in a single file, and every agent appended to its
tail. Two branches that both append hit the same last hunk, so git cannot
auto-merge them: the second one to be reviewed conflicts, and so does the third, and
the fourth. Measured on 2026-09-29: four of the five open PRs were unmergeable, and
DECISIONS-LOG.md was the only conflicting file in all four:
#22 fix/crafty-oauth2-proxy-signin CONFLICT (content): DECISIONS-LOG.md
#20 feat/conformance-job-template CONFLICT (content): DECISIONS-LOG.md
#19 feat/conformance-trigger-kubeconfig CONFLICT (content): DECISIONS-LOG.md
#18 feat/conformance-runner-image CONFLICT (content): DECISIONS-LOG.md
#17 feat/ci-is-the-approver clean (it touched no log entry)
Nothing was wrong with any of those changes. The log's storage format serialised work that was otherwise parallel, and it got worse with every concurrent branch: N branches produce N-1 rebases, each of which invalidates any gate run that preceded it.
The fix is the obvious one for concurrent appenders: stop sharing a file. Each handoff is its own file. Two agents writing handoffs touch disjoint paths, so there is nothing for git to merge and nothing to conflict. This scales to any number of parallel branches with zero coordination — which is the point, since the agents are deliberately isolated from each other in separate worktrees and cannot coordinate.
There is deliberately no index file and no counter. An index would be a shared
mutable file — exactly the thing that just failed — and a sequence number would have
two agents racing for 0043. The directory listing is the index.
Writing an entry
One file per handoff, named:
decisions/YYYY-MM-DD-<slug>.md
<slug> is lowercase [a-z0-9-]. Use your branch name's last segment — it is
already unique per unit of work, which is precisely the property the filename needs.
A branch fix/crafty-oauth2-proxy-signin handed off on 2026-09-29 writes:
decisions/2026-09-29-crafty-oauth2-proxy-signin.md
The file is YAML frontmatter followed by three required sections:
---
date: 2026-09-29
branch: fix/crafty-oauth2-proxy-signin
title: The Keycloak gate works — Crafty's own login was the wall
---
## What changed
Prose. What you actually did, and why.
## What I verified
The measurements, with their numbers. Quote the field you read, not the prose you
believed. Name the gate result and its exit code.
## What I did NOT verify
Everything else. An honest "UNVERIFIED" is worth more than an optimistic "green" —
this repo has been burned by the difference more than once.
All three headings are required and enforced (ci/decisions-log.sh). They are
CLAUDE.md §7's contract; making them a checked structure is what stops an entry
degrading into "done ✅".
Reading the log
The whole log, oldest first:
ls decisions/[0-9]*.md | sort
The current PM handoff — the newest entry. Ties within a day are broken by what landed
on main last, which is the honest answer, so ask git rather than the filename:
git log --diff-filter=A --format='%H' --name-only -- 'decisions/[0-9]*.md' \
| grep '^decisions/' | head -1
For a quick skim of who said what:
grep -H '^title:' decisions/[0-9]*.md | sort
The archive is frozen
DECISIONS-LOG.md is read-only history. Its SHA-256 is pinned in
decisions/ARCHIVE.sha256 and ci/decisions-log.sh fails the merge gate if the file
changes. That is not ceremony: without it, the next agent to read runbooks/ or an old
CLAUDE.md habit appends to the tail again and re-creates the conflict for everybody
else, silently, one PR at a time.
If the archive genuinely must change (a leaked credential to redact, say), that is a
deliberate, reviewed act: change it, run sha256sum DECISIONS-LOG.md > decisions/ARCHIVE.sha256,
and say in your handoff entry why. Re-pinning is visible in the diff. Appending is not.